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La capacità di affrontare e risolvere problemi è ampiamente riconosciuta, sia in contesto internazionale (NCTM, 2020) che nazionale (MIUR, 2012), come una delle competenze matematiche più importanti da sviluppare negli studenti duran- te il loro percorso scolastico in matematica—non solo, naturalmente—e da por- tarsi come bagaglio per la vita. Nonostante i traguardi per competenze delle In- dicazioni Ministeriali per il primo e secondo ciclo facciano esplicitamente riferi- mento alla competenza di problem-solving, l’impressione è che la risoluzione di problemi sia ancora la cenerentola dell’attività matematica a tutti i livelli scolari: sembrano prevalere, talvolta in modo quasi esclusivo, le attività che richiedono un approccio riproduttivo, piuttosto che quelle che mettono in gioco il pensiero produttivo. In questo articolo parleremo di una metodologia di lavoro con il problem-solving matematico, sviluppata da Peter Liljedahl (Simon Fraser University, Vancouver, Canada): la Mathematical Thinking Classroom, metodologia che ha sperimentato per anni e descritto in un libro (Liljedahl, 2020). Durante un recente periodo di visiting del professore canadese presso il nostro Dipartimento di Matematica e Applicazioni «R. Caccioppoli» dell’Università degli studi di Napoli Federico II, abbiamo avuto l’opportunità di osservarlo condurre attività coerenti con l’approccio della Thinking Classroom con studenti dell’indi- rizzo didattico. In questo articolo, dopo una breve descrizione di tale approccio, lo esemplificheremo a partire dall’esperienza di due studenti.

The dissemination of cancer cells to local and distant sites depends on a complex and poorly understood interplay between malignant cells and the cellular and non-cellular components surrounding them, collectively termed the tumour microenvironment. One of the most abundant cell types of the tumour microenvironment is the fibroblast, which becomes corrupted by locally derived cues such as TGF-β1 and acquires an altered, heterogeneous phenotype (cancer-associated fibroblast, CAF) supportive of tumour cell invasion and metastasis. Efforts to develop new treatments targeting the tumour mesenchyme are hampered by a poor understanding of the mechanisms underlying the development of CAF.Here we examine the contribution of microRNA to the development of experimentally-derived CAF and correlate this with changes observed in CAF derived from tumours. Exposure of primary normal human fibroblasts to TGF-β1 resulted in the acquisition of a myofibroblastic CAF-like phenotype. This was associated with increased expression of miR-145, a miRNA predicted in silico to target multiple components of the TGF-β signaling pathway. miR-145 was also over-expressed in CAF derived from oral cancers. Over-expression of miR-145 blocked TGF-β1-induced myofibroblastic differentiation and revert CAF towards a normal fibroblast phenotype.We conclude that miR-145 is a key regulator of the CAF phenotype, acting in a negative feedback loop to dampen acquisition of myofibroblastic traits, a key feature of CAF associated with poor disease outcome.

La nostra ricerca vuole mostrare come lo studio di approcci sviluppati in diversi contesti culturali può essere importante per riflettere sulle nostre pratiche didattiche e per progettare nuove sperimentazioni nelle classi. In particolare abbiamo studiato le rappresentazioni grafiche usate per descrivere e risolvere problemi additivi nella scuola primaria in Russia e Cina. In questo articolo introdurremo l’idea di trasposizione culturale che sarà anche esemplificata attraverso la descrizione e analisi di due percorsi didattici realizzati in una II e in una V primaria italiane.

New biological tools are required to understand the functional significance of genetic events revealed by whole genome sequencing (WGS) studies in oesophageal adenocarcinoma (OAC). The MFD-1 cell line was isolated from a 55-year-old male with OAC without recombinant-DNA transformation. Somatic genetic variations from MFD-1, tumour, normal oesophagus, and leucocytes were analysed with SNP6. WGS was performed in tumour and leucocytes. RNAseq was performed in MFD-1, and two classic OAC cell lines FLO1 and OE33. Transposase-accessible chromatin sequencing (ATAC-seq) was performed in MFD-1, OE33, and non-neoplastic HET1A cells. Functional studies were performed. MFD-1 had a high SNP genotype concordance with matched germline/tumour. Parental tumour and MFD-1 carried four somatically acquired mutations in three recurrent mutated genes in OAC: TP53, ABCB1 and SEMA5A, not present in FLO-1 or OE33. MFD-1 displayed high expression of epithelial and glandular markers and a unique fingerprint of open chromatin. MFD-1 was tumorigenic in SCID mouse and proliferative and invasive in 3D cultures. The clinical utility of whole genome sequencing projects will be delivered using accurate model systems to develop molecular-phenotype therapeutics. We have described the first such system to arise from the oesophageal International Cancer Genome Consortium project.

Since several years, politicians, researchers and educators from different countries are debating on possible reasons for the success of Confucian area students in interactional assessment projects (such as PISA). Starting from the study of teaching practices developed in this East area, in Italy we developed an educational research based on the process of cultural transposition (Mellone & Ramploud, 2015). With this term we mean the process of change that develops considering two or more cultural-educational backgrounds with the aim to maintain their differences without “translating” them from one culture to another, but rather highlighting these in order to review their meaning processes and daily use in classrooms. In this article we present two educational experiences developed in a second and fifth grades Italian classroom on the cultural transposition of the pictorial equations approach of the Chinese curriculum inserted in the typical structure of Chinese word problems, called problems with variation (Bartolini Bussi et al., 2013). According to Cai and Knuth (2011) in China this symbolic representation is used since the early school years as a possible support for “constructing” a bridge to the “informal algebra”. In the Russian curriculum it is possible to find an analogous approach called intermediate strategies of graphic representation (Davydov, 1982) referred to similar pictorial equations. Our experience of cultural transposition in the Italian context have shown the potentialities of the use of problems with variation as well as the crucial role of the figural equation.

Poster Abstract

Editoriale BIOS

Several studies have reported that high sodium (Na) intake increases not only urinary Na but also urinary calcium (Ca), suggesting that high Na intake could be involved in the pathogenesis of hypercalciuria. No research data are available on the relationship of Na intake to the prevalence of hypercalciuria within the general population. Moreover, it is not clear if Na intake relates only to urinary Ca or also to other indices of Ca homeostasis, including intestinal Ca absorption. In the present paper, two distinct studies addressed these points using 24-hour urinary Na as an index of salt intake in individuals on their habitual unrestricted free diet. Study 1 analyzed the relationship between 24-hour urinary Na and hypercalciuria (24-hour urinary Caor = 7.5 mmol in men,or = 6.25 mmol in women) in a population sample of 203 men and women, aged 20-59 years. Study 2 analyzed the relationship between 24-hour urinary Na and intestinal strontium (Sr) absorption, used as an index of intestinal Ca absorption, urinary (24-hour and fasting) and plasma Ca, and plasma parathyroid hormone in 36 healthy men and women, aged 18-65 years. Within the population sample (study 1), 24-hour urinary Na was directly and significantly correlated with prevalence of hypercalciuria when controlling for gender, age, weight, and urinary creatinine: the relationship was continuous and linear for urinary Na ranging between 40 and 200 mmol/24 h. In the 36 volunteers (study 2), 24-hour urinary Na was related to 24-hour and fasting urinary Ca (p0.001) but not to intestinal Sr absorption: the relationship between 24-hour urinary Na and urinary Ca (both 24 h and fasting) was also significant, controlling for other variables. The results indicate that in adults on their habitual diet, urinary Na, which reflects dietary salt intake, correlates with the prevalence of hypercalciuria independently of intestinal Ca absorption and mainly via renal mechanisms.

According to modern trends of research in mathematics education, attitude towards mathematics is a very important construct to interpret students’behaviour. In this paper we present a one-year experiment carried out in a 12th grade classroom in Naples (Italy) finalized to change students’attitude towards mathematics (the classroom was characterized by low interest in mathematics). We will describe the pashes of the research experiment and then describe and comment upon the obtained results.